1. Field of the Invention
This invention relates to a fusible member of a fusible link element used as a large-current fuse.
2. Description of the Related Art
FIG. 8 shows an overall construction of one conventional fusible link element 1 of a fuse structure used in a connector for connecting a wire harness in an automobile or the like, and this fusible link element includes a pair of opposed female terminal portions 2, and a retaining piece portion 3, stamped and directed upwardly, is formed on an outer surface of each female terminal portion 2. A relatively-wide base portion 4 extends upwardly from an outer wall of each female terminal portion 2, and a bent portion 5 extends from the base portion 4. A laterally-extending portion 6 is formed at a distal end portion of one of the bent portions 5, and a tin alloy chip 7, having a narrow width corresponding to a predetermined melting capacity, is provided adjacent to the laterally-extending portion 5. Upwardly-projecting portions 9 are forcibly deformed to embrace the tin alloy chip 7 to provide a fusible member 8. Thereafter, the tin alloy chip 7 is melted or fused to the fusible member so as to stabilize melting characteristics of the fuse.
In the above fusible link element, the upwardly-projecting portions 9 are forcibly deformed by pressing to hold the tin alloy chip 7. A high-precision technique is required for securing the soft tin alloy chip to the fusible member during the pressing of the fusible member. And besides, in order to stabilize the melting characteristics of the fuse, the tin alloy chip is heated to a certain temperature, and then is fused to the fusible member. In this fusing step, the tin alloy chip must be prevented from being overheated so that the tin alloy chip will not flow away from the fusible member, and therefore a relatively high technique is required for controlling this fusion temperature, and therefore in the manufacture of the fusible link element, such a fusion step, together with the pressing step, greatly lowers the productivity of the fusible link element. The tin alloy portion thus formed is exposed at its surface to the air, and therefore is susceptible to oxidation.